Sound reproducing apparatus



Dec. 9, 1941.

R. E. BOWLEY SOUND REPRODUCING APPARATUS Filed Feb. '5, 1940 INVENTOR" Patented Dec. 9, 1941 SOUND REPRODUCING APPARATUS Raymond E. Bowley, San Anselmo, Calif.; Eve Mary Bowley Administratrix of said Raymond E. Bowley, deceased Application February 5, 1940, Serial No. 317,266

9 Claims.

This application is a continuation in part of my U. S. Patent No. 2,189,161, issued February 6, 1940, for Sound reproducing apparatus. This invention is also a modification of the apparatus described in my said Patent 2,189,161, carrying forward the basic idea therein disclosed.

An object of the invention is to provide improved sound reproducing apparatus adapted for bringing out a wider range of audio frequencies wherein the overtone frequencies are more effective in producing improved articulation, improved intelligibility and improved tone sensations upon the ear of a listener.

An object of the invention in particular is to provide sound reproducing apparatus as described in the preceding paragraph, whereby persons who are hard of hearing or who are partially deaf and in some cases whereby persons who are deaf have their sense of hearing improved, by the use of the apparatus comprising this invention.

Another object of this invention is to provide apparatus as described above particularly adapted for use by persons having a defective sense of hearing and by persons partially deaf.

Another object of the invention is to provide apparatus comprising sound reproducing apparatus and an electrical and electro-magnetic circuit network adapted for accomplishing and carrying out the objects mentioned in the preceding paragraphs.

Other objects and features of my invention more or less apparent and too numerous to relate in detail, will appear from the description of my invention in the following specification and accompanying drawing, taken together or separately.

For the sake of explaining the principles of my invention, I will now describe illustrative embodiments thereof. The drawing is for illustrative purposes only and is not drawn to scale.

The details of mechanical construction being left to the skill of the experienced workman employing the method and apparatus herein described and claimed.

In the drawing:

Figure 1 is a complete operative apparatus in the class described embodying one modification of the invention.

Figure 2 is apparatus in the class described embodying another modification of the invention.

Figure 3 is apparatus comprising an electrical and electro-magnetic wiring circuit network embodying my invention.

Figure 4 is another modification of apparatus in the class described embodying a modification of the invention, wherein an electrical and electro-magnetic circuit; network embodying the invention is connected in the output circuit of an electron discharge device.

Figure 5 is another modification of the invention, wherein apparatus in the class described includes the circuit network comprising my invention connected in the input circuit of an electron discharge device.

One feature of my present invention is to cover themethod and apparatus carrying forward the basic idea disclosed in my U. S. Patent 2,189,161, issued February 6, 1940.

Another feature of my present invention is to cover the method and apparatus for improving the timbre and clarity of reproduced sound waves shown and described, in general, in sound reproducing apparatus, in telephone apparatus, in sound communicating apparatus, and in apparatus for recording sound, including radio apparatus and other electronic apparatus for translating sound Waves or electrical currents having audio or associated frequencies in cooperation with a sound translating device or with a sound reproducing device, or with both a sound translating device and a sound reproducing device.

Referring to the drawing:

In Fig. 1 a complete operative apparatus is shown, adapted for sound communication or for reproducing sound waves comprising in combination, an input sound translating device or microphone I, an electrical and electro-magnetic circuit network including a step up or amplifying audio frequency transformer 2 having a primary winding 3 and a secondary winding 4, powersuitable sound reproducing device and which may be either of the magnetic, electro-magnetic,

electro-dynamic, permanent-magnet-dynamic, or'

other type II), and an electrical and electromagnetic cooperative circuit network connected in the input circuit of the wiring circuit comprising, an inductance having a plurality of coil windings I2-l3, tapping points I l-l5 at opp0-- site ends of the inductance and an intermediate tapping point I 6 or [9 also provided'on the inductance, two of said tapping points, as I4 and l6l9 operatively connected in series with the primary or input circuit, a suitable impedance, which may be a resistance unit IT, a condenser l 8, or both, having one end connected to the other tapping point, as I6, the opposite end of the inductance connected to a suitable portion of the wiring circuit network having direct connection with either of the said tapping points H5 or l9 connected to the circuit network, as

The apparatus shown in Fig. 1 is a modification of the apparatus described in my Patent No. 2,189,161, issued February 6, 1940,- but the specific combination is a different construction 'anda different arrangement comprising another species of the said invention. The principle of operation of the wiring circuit I l is described inmy application 217,459, now U. S. Patent No. 2,189,161. In this invention the apparatus is particularly adapted to function as sound communicating apparatus ortelephone apparatus as well assound reproducing apparatusiand sound recording apparatus. v

, Fig. 2 is apparatus. in the class described in the preceding paragraph, wherein the sound reproducing, device "J or loud speaker l shownin Figure 1 may be. employed, or a'modificationof one or another of the sound reproducing devices or loud, speakers described and claimed.in my ILS. Patents Nos. 2,189,161 issued February 6, 194 0; or 2,178,030 issued October 31,1939, may be used, or a modification of the apparatus described in my U. S. Patents, Nos. 20,395 issued Junev 8, 1937, or 20,467 issued August 17, 1937, may be used. 7 1

IA is a microphone or other sound transmitting device;ppower supply apparatus 5A may be batteries, or electrical power supply from a suitable source, or a rectifier of suitable type for use with A. 0. power supply means; 6 is a controllingv switch; 9A is the output circuit; in addition to theoutput circuit 9A being adapted for attachment to a sound reproducing device, the apparatus comprising this invention may also be connected to sound recording apparatus, radio broadcast systems and other apparatus. adapted for translating, transmitting orreproducing sound waves. 7

A cooperative. electrical andelectro-magnetic circuit network as described in Figure 1 is shown bynumeral l I, but in this modification of the invention the impedance comprises a resistance unit l1 and a condenser l8 in parallel arrangement. 1

A feature of my present invention is embodied in the second electrical and electro-magnetic circuit network including a plurality of coil windings I241 and is. forming an inductance having,

cuit network 26 at points. 22 and 23., and also hav ingan intermediate tapping point IS; a suitable impedanoe llA lliA, which may be a resistance unit l'lA, a condenser lllA or both llA-I8A, having anendconnected to the intermediate tapping point, the other end of the impedance being connectedto ajsuitable portion of the. Wiring cir-. 4 I either end of theindu'ctancefa s point 25. r

In Figure3 apparatus in theclass described is shown comprising an electrical andelectro -magneticfcircuit network 26 including the circuit net- Work-2| described in Figure iwherein the pedance is a resistance unit IlA, the inductance 2| has a plurality of coil windings i2A-l 3A, tapping points 22-23 are provided at each end of the inductance 2| and an intermediate tapping point I9 is also provided, one end of the impedance HA is connected to the intermediate tapping point, the other end of the impedance is connected to one end of the inductance at point In Fig. 4, apparatus in the class described is shown comprising electron discharge device 21 and an electrical and electro-magnetic wiring circuit network including the cooperative electrical and electro-magnetic circuit network 2| of this invention connected in the output or plate circuit of the" electron discharge device. pedance lflA'as described in Figures 2 and 3 comprising a'condenser 18A is connected to one end of the inductance 2! at point 23 and also connected to the inductance at the intermediate tapping; point l9. The apparatus may be radio apparatus, electronic amplifying apparatus... etc, adapted for transmitting, translating, amplifying or reproducing sound waves, or for carrying cur-v rents having frequencies corresponding to audio frequency, radio frequency or' associated frequency vibrations.

InFig. 5 the apparatus described in Fig. 4 is shown embodying another modification of the invention comprising an air core transformer 28 having a primary winding P and a secondary Winding S, an input circuit 2 9 connected to the primary winding, the secondary winding em; bodies the inductance circuit 2] shown in the co- I operative. electricaland elec tro-magnetic circuit network 2| Fig. 2 and including the imped, ance HA and 18A connected in theinputor grid 7 circuit of the electrondischarge device'zlA.

, 'Ihe'microphone or other suitable inputsound translating device or sound reproducing device lA;shown in Figure 2 is a modification of theapa abl de r b d l n one r recf myU. SI Patents or applications for U; S. Letters Patent here ment o e u. s. Patent No.;1,93 {l, 693

issued November 14, 1933, and reissued a Re. Patent "No. 20,467 August 17, 1937; or in U. S. Patent N0. 1,9'7(),837 issued August 17, 1937 and reissued as R e Patent No. 20,395 June 8, 1937, or in U. s. Patent No. 2,178,030 issued Oct. 31,1939; or in U. S. Patent No. 2,189,161 issued February 6, 194:0; or in copending application for Letters Patent 'in th'e U1,S.Seifial No.361,593,flfi1ee;0 t ber 17, 1940, whi ch is a division of this applica tion.

Q My copending application, Serial No. 331,837, filed April 26, 1940, is a division of this applica tion.

Theembodiments of the invention illustrated and described herein have been selected for. the purpose of setting forth theprinciples involved.

The invention "is, however, susceptible to being ma mamearq meet different conditions encountered in itsuse without departure frqrn the;

inventive concept disclosed. W q

Numerous ideas have been carried out this invention, with recognition on my;part that;one

or i I1. 'V l m n angemen s. o 9 9; binations can be employed separately,-or thevare ious elements, arrangements or combinations can be ernployed; collectively. Different -coInbina'-.

tions or arrangements of the Wiring circuit networks and apparatus herein described produceja An imrangenients, therefore I' Want it understood that I do not limit my invention to the particular apparatus illustrated, or shown for illustration purposes, for the obvious reason that different 'people have different tastes for music and demand different tone qualities and also for the obvious reason that the sense of hearing of different people is different and therefore requirements in the application of this invention ar varied accordingly.

I realize that other modifications of this invention are possible, therefore I say my invention is not limited by the detailed constructions shown and described, and it is my intention to cover all other modifications which can be made without departure from the spirit of the invention or the scope of the claims.

I claim:

1. Apparatus constituting an electrical and electro-magnetic coupling and compensating network, comprising the combination of a choke coil winding divided by tapping the winding, a lead connected to the winding at the intermediate tapping point, a second lead connected to one end of the coil winding, the leads providing means for connecting the coil Winding in the circuit network, the opposite end of the coil winding being free of leads for connecting to the associated circuit network, a fixed resistance and a fixed condenser in parallel forming an impedance having one end thereof connected to the free end of the coil winding, the opposite end of the impedance connected to the coil winding and also to one of said leads at either the intermediate tapping point or at the opposite end of the coil winding, and a second choke coil winding connected in series with a lead of the said coupling and compensating network in cooperation with the above described inductance and impedance combination, comprising a choke coil forming an inductance having a plurality of windings, tapping points at the ends of the inductance coil and an intermediate tapping point at the junction of two of said windings, a suitable impedance, comprising a fixed resistance and a fixed condenser in parallel, one end of the said impedance connected to the intermediate tapping point of the choke coil, the two end tapping points connected in series with a lead of the said coupling circuit network, the opposite end of the said impedance connected to a suitable portion of the coupling circuit network in direct connection with one of the said end tapping points of the said inductance connected to the coupling circuit, the impedance being in shunt with a portion of the second said choke coil and in series with the unshunted portion thereof in the coupling network, the intermediate tapping point being free of other circuit connections.

2. An electrical and electro-magnetic coupling and compensating network in apparatus in the class described comprising, an inductance having a plurality of windings, tapping points at ends of the inductance coil and an intermediate tapping point at the junction of two of said coil windings, a fixed resistance shunting one portion of the divided winding forming a suitable impedance, one end of the said impedance connected to the intermediate tapping points, the two end tapping points of the divided winding having leads for connecting to suitable portions of the said network, the opposite end of the said impedance connected to one of the end tapping points of the divided winding, the impedance shunting a portion of the divided winding and being in series with the unshunted portion thereof, the intermediate tapping point being free of other circuit connections.

3. An electrical, electro-magnetic and capacitive coupling and compensating network in apparatus in the class described comprising, an inductance having a plurality of windings, tapping points at'endsof the inductance coil and an intermediate tapping point at the junction of two of said windings, a condenser shunting a portion of the divided winding forming a suitable impedance, one end of the said impedance connected to-the intermediate tapping point, the

end tapping points of the divided winding having leads for connecting to suitable portions of the said network, the opposite end of the impedance connected to one of the end tapping points of the divided winding, the impedance shunting a portion of the divided winding and being in series with the'unshunted portion thereof, the intermediate tapping point being free of other circuit connections.

4. An electro-magnetic and capacitive coupling and compensating network in apparatus of the class described comprising an inductance having a plurality of windings, tapping points at the ends of the inductance and an intermediate tapping point at the junction of two of the said windings, a fixed resistance and a condenser in parallel forming a suitable impedance, one end of the impedance connected to the intermediate tapping point of the divided winding, the opposite end of the impedance connected to one of the said end tapping points of the divided winding, the impedance shunting a portion of the divided winding and being in series with the unshunted portion thereof, the intermediate tapping point being free of other circuit connections.

5. The combination of an electro-acoustical device in the class described and a coupling and compensating network connected in operative relationship with the electro-acoustic device comprising two inductance and impedance network combinations in the class, described, one of the said inductance and impedance combinations forming an inductance having a winding divided by tapping the winding, tapping points at ends of the inductance and an intermediate tapping point at the tapped connection, a fixed resistance and a condenser in parallel forming, a suitable impedance, one end of the impedance connected to the intermediate tapping point, the opposite end of the impedance connected to one of the end tapping points of the said divided winding, the impedance being in shunt with a portion of the said divided Winding and in series with the unshunted portion thereof in the coupling network, the intermediate tapping point being free of other circuit connections, circuit leads of the said inductance and impedance network combination connected to the circuit leads of the electroacoustic device.

6. In an electro-acoustical network system, an electrical and electro-magnetic coupling and compensating network comprising a choke coil forming an inductance divided by tapping the winding, tapping points at the ends of the inductance and an intermediate tapping point at the tapped connection, a fixed resistance and .a fixed condenser in parallel forming an impedance, one end of the impedance connected to the intermediate tapping point, the opposite end of the impedance connected to one of the end tapping points of the inductance, the end tapping points connected in series with a lead of the coupling network, the impedance shunting a portion of the choke c011 and being in series withthe. unshunted portion thereof, the intermediate. tapping point being free of other circuit connections. v i

'7. An: electrical and electro-magnetic coupling and compensating network combination connected in a circuit in apparatus in the class described comprising an air core transformer having a pri'- mary. winding and a secondary winding, the secondary winding, formingan inductance divided by tapping the winding; tapping; points at the outer ends of the secondary inductance and an intermediate tapping point at the tapped connection, a suitable,impedance,ycomprising a fixed resistance and-a condenser parallel, one end of sthe impedance connected to the intermediate tapping point of the secondary winding, theother end of the impedance connected; to one of the end tapping points of the secondary winding, the impedance shunting a portion of, thesecondary winding and being'in series ,withthe unshunted portion thereof, the intermediate tapping point being free of other circuit connections.

8. 'An electrical and eleetro-magnetic coupling and compensating networkcombination connected in a circuit inapparatus in the class described comprising a' transforrner havinga primary Windingand a secondary Winding, one of said windings divided into two portions at an inte rmediate tappingpoint, tapping points at the ends ofthe divided inductance winding and an intermediate tapping point at the junctionof the two said winding portions, a fixed resistance and a condenser inv parallel; each having. one end i in con+ HBGtiOIlfWith the intermediate tapping point,- the other end ofthe resistance andicondenser con-' nected tosone of the said endtapping points :of the divided transformer winding, circuit. leads connected to the said end tapping points, the re? sistance *and condenser fparallel arrangement shunting a portion of the v: divided; winding and being in series 1 with -the -.unshunted portion thence of, th'e intermediate tapping pointbeing; free of other;circuitconnections;

9. In: apparatus for, improving the/sense, of hearing for personshaving defective hearing, an inductance having, a plurality of windings divided by tapping the inductance, electrical and electromagnetic circuit network comprisingacooperative electrical and electro-magnetic circuit netw r includin an inducta c t p ing points at the ends" of the ind ctance and van intermedi tapping; point atv theijunction of two of-thesaid di s, a fixedrresistance nd. a fixed condenser in parallel forming an impedance oneend of the impedanQ onnected to the intermediate tapping point; the other end of the impedance connected to, oneof thesaid end-tapping points, the end tapping points connected to the network system, the impedance'shunting a portion of the I inductance and being in" series with the unshunted portion of the divided winding, the intermediate tapping point beingfree of other circuit connections.

V RAYMOND E. BOWLEY. 

